Humidifying apparatus and means for controlling the same.



J. I. LYLE & E. T. MURPHY. HUMIDIPYING APPARATUS AND MEANS FORCONTROLLING THE SAME.

. v APPLIOATION FILED MAR. 22, 1911. Q v 1,01 1,458. Patented Dec. 12,1911.

3 SHEETS-SHEET 1.

i i BY' I ATTERNEYS J I. LYLE & B. T. MURPHY. HUMIDIFYING APPARATUS ANDMEANS FOROONTROLLING THE SAME,

I APPLICATION FILED MAR. 22, I911. i 1,01 1,458." Patented Dec. 12,1911.

. 3 SHEETS-HEET 2.

, WITNESSES: 1 M\\\\\A m 1% ,myons um lml lmlm I Jllll NR. I 1 BY. 7 I

AT RNEYS J. L'LYLE & E. T. MURPHY. HUMIDI PY ING APPARATUS AND MEANS FORCONTROLLING THE SAME.

- APPLICATION FILED MAB., 22, 1911.

' Patented Deb. 12, 1911.

3 SHEE'TPSHEET a.

' WITNES SESi 73 'ATTOR EYS 1 JOEL IRVINE LYLE, or

PHILADELPHIA, ,.PE vNsYI-au ivm PIi AINFIELD, new JERSEY, ANflEDWARh-T.memento:

' nuivirnrrrmenrranarus AND MEANS iron CONTROLLING- THE sA riE.

To all whom it ma mm:

Be it known that we, JOEL IRvINr; LYLE, a citizen of 'the'United Statesof America, and

a resident of Plainfield, county of Union,

and State of New Jersey, and EDWARD T MURPHY, a citizen of the. UnitedStates of --county of Philadelphia, and State of Penn America,'and aresident of Philadelphia,

sylvania, have invented certain new and useful Improvements inHumidifying Ap-' paratu's and 'Means for Controlling the Same, of whichthe following is a specification, reference being had to theaccompanyt.ing drawings, forming a part thereof. 1 taining a uniform. moisturecontent in air,

regardless of its pressure ortemperature. In metallurgical processes,such as those Our invention'relates to means for maincarried out. inBessemer converters, blast furnaces, and the like,'wherein compressed"air is passed through'the molten metal, the

' -varying conditions encountered render necemployed. The moisturecontent thereof, .,.the ratio of the moisture to the air by quantity orweight.the number of grains of essary the varying of the pressure oftheair "moisture .per pound of air-Should however 1 be kept uniform 'inaccordance withthe predetermined requirements, yet it must :be

borne in mind that the amount of moisture 4 contained in dry. saturatedair, '5. e., dry air I *at' its dew point, depends Wholly upon the.,;temperature of the air andnot at all upon. its pressure. For example,dry saturated air at '.31 degrees temperature Fahrenheit will carryalmost exactly two grains of'moisture per cubic foot. Compress anyamount of 'air into a single cubic foot of space, or 'rarefy the air insuch space, and provided the same.

temperature of 31 degrees ahrenheltbe maintained,- the same two grams ofmoisture will be the limit carried by the air when dry and fullysaturated. Raise the-temperature. of'the air at anypressure to say,degrees Fahrenheit, and the amount of moisture car'- ried under similarconditions of dryness and .saturation (2'. e. air at its dew point butwith no free entrained Water),.will"be almost exactly four grains foreach cubic foot of space occupied.

-. As it is desirable for-the sake of economy 'to regulate themoisture'content of. the .air after its 'compres'sion'rather. thanbefore it,.

; and the desiredmethod. of determining the moisture content i i-theair-is to cool the air Application filed Mamnaa 911. Ser'ia1 No. 6 16,077.

its dew"point, and the of. is as follows:

degrees Fahrenheit. I v

'Spe'cificationof Letters Patent,- fPatenf e d Dec, 1911 after'icompression' to a. predetermined-point, and to sat-urate'at suchpoint,it will-follow that to provide for a uniform predetermined ing airpressures it becomes necessary to moisture content underconditions ofvaryvary the tem erature'of the air at the time I it is saturate as thepressure thereof varies.

This wouldbe'a simple matter if. the re quired temperature variationsweredirec'tly 1 proportionate to'the pressure variations, but

For example,

unfortunately theyv are not. assumethat the predetermined. moisturecon-j tent required be 21.5 grains of water vapor for each pound of air,the required'relation ship between the temperature of the air at gagepressure there- Temperature in per square 'mch.

36 as as 7.95

Gage pressure in pounds V To, overcomethejditficulty thus presented 1means operated bytherelative variation of it has been suggested in thepast to provide acompensating means in conjunction. with the pressure:andtemperature of the air treated, so that the temperature thereof willbe varied in the proper proportion to the 'variationspressurethereof,'.to'efiect the result required. Such compensating-means is undesirable, however,.- as lending 'additional and unnecessarycomplication to the apparatus,.and it is the object of our presentinvention to so design, arrange, construct and equip the apparatus.asto'renderits use unnecessary 'We accomplish this. by theemployment'of difl'erentially operated fluid.

jected upon one side totthe pressure of the air beingtreated, andupon.the other side pressure means for controlling-the tempera; 'ture of theair, the said means beingv sub 3 100.

to the pressure of the'fluid, such as" sulfur. n

dioxid,-whos e expansion or increased pressure due toztemperatureincreases, wlthln the limits required, is substantially directlyproportionate to the increase of theair pr'essure requiredundercorresponding temperature'increases of the"'air,'.to maintain therequired substantially uniform moisture content in-theair at its dewpoint, the said fluid being subjected to the temperature of the air atits dew point, so that it varies directly as the temperature of the airvaries. As it is desirable that the apparatus be adjustable so that theamount of moisture to a given quantity of air may be predeterminedlyvaried, the said dilferential fluid pressure operated means may includea lever mechanism whose ratio may be varied at will, by hand, in favorof the air pressure or the temperature controlled fluid pressure, and aspring whose tension may also be varied.

-In addition to the broad features of.invention herein, many'novelfeatures of construction and combinations of parts, such as will befully pointed out hereinafter, are also included, and in order that ourinven- I .tion may be fullyunderstood we will now proceed to describe anembodiment thereof,

having reference to the accompanying drawings illustrating the same, andwill then point out the novel features in claims.

In the drawings: Figure 1 is a view generally in side elevation of anapparatus con structed in accordance with our invention, certain partsbeing broken away and other parts shown in central vertical section.Fig. 2 is a view in front elevation upon an enlarged scale of theregulating device employed, showing also a portion of the cooler towhich it is attached, Fig. 3 is a view in central vertical longitudinalsection through the parts shown in Fig. 2. Fig. 4 is a top view of theregulator with a portion of the cooler shown in horizontal section. Fig.5 is a detail view in horizontal transverse section, upon the line 55 ofFig. 3. Fig. 6 is a diagrammatic view showing the characteristic curvesrepresenting the theoretical balancing value required for changes inpressure of the air being treated, together with the actual balancingvalue obtained in the use of the apparatus herein described,illustrating the same in connection with several relative humidities tobe obtained.

The apparatus shown consists, in general, of a blowing engine 10arranged to compress atmospheric air to the required extent, ahumidifying and cooling apparatus 11 for receiving compressed air, andwhich may be termed a dew point cooler because of the fact that it isarranged to cool the air and deliver it at the required temperature in afully saturated condition, and a regulator 12 for controlling thecooling apparatus in such a way as to determine the temperature at whichthe air is delivered therefrom. The air delivered from the dew pointcooler will be conveyed to a Bessemer converter, blast furnace, or otherapparatus in which it is to be employed, as will be well understood.

The dew point cooler comprises a substantially cylindrical shellincluding a chamber 13 in which are arranged a plurality of pipes 14having spray nozzles therein, the pipes 14 constituting branches from asupply pipe 15 through which relatively cold water will be delivered forthe purpose of cooling the compressed air delivered to the chamber 13from the blowing engine 10, and supplying moisture thereto. Eliminatorplates 16 are conveniently arranged near the forward end of the dewpoint cooler in order to entrap any entrained water, whereby the airdischarged through the delivery pipe 17 will be dry, though thoroughlysaturated, that is to say, while it will be at the dew point it willcarry no free water with it.

The cooling water is supplied to the pipe 15 by means of a pump 18 orother suitable means, the supply pipe 19 of the pump connecting with therefrigerating device or other means from which water may be received ata low temperature. The dew point cooler is provided with a dischargepipe 20 for carrying away the water therein which has been used forcooling purposes, the temperature of which has been raised by itscontact with the heated air. This pipe communicates through a water seal21 with a return pipe 22 such as may lead back to the refrigeratingmachine to be again cooled therein, and then resupplied through the pipe19 to the circulating pump 18. The return pipe 22 is provided with abranch 23 which leads to a mixing valve 24 arranged in the supply pipe19. The mixing valve 24 is of such a character that in one position itwill afford direct and open communication through the supply pipe 19 tothe pump 18, cutting off communication from the branch pipe 23therewith; in another position it will open communication between thebranch pipe 23 and the portion of the supply pipe 19 leading from themixing valve 24 to the pump 18, closing communication between thisportion of the supply pipe and the portion thereof upon the other sideof the mixing valve 24; and in intermediate positions it will open bothof the said connections in varying proportions. By this it will be seenthat water at any temperature from that of the fully cooled water fromthe refrigerating or other apparatus, to that of the relativelyheated-return water from the dew point cooler, may be supplied to thepump 18 in accordance with the position of the valve 24. The position ofthis valve is regulated by means of a fluid pressure motor 25 and theoperation of the said fluid pressure motor 25 is controlled by means ofthe regulator 12. This regulator or controlling device includes a casing26 which is secured to the shell of the dew point cooler, and isprovided with a perforated tubular extension 27 which passes into theinterior of the dew point cooler, being disposed in the path of the aircurrents therethrough after they have been cooled. The casing forms asupport for two expansion chambers 28 and 29, the latter of which is inopen communication through a channel '30 with the hollow inte pipe 31with a closed chamber 32 located within the tubular extension 27. Theexpansion chamber 29 is thus in open and constant communication with thecompressed air in the dew point cooler and is therefore I directlyinfluenced by the pressure ofsuch air, while on the other hand theexpansion chamber being in communication with a closed chamber 32, is innowise directly affected by the pressure of the air. The chamber 32 isarranged to contain, however, a volatile liquid and as the said chamberis in direct contact with the cooled and compressed air in the dew pointcooler it will follow that the pressure of the volatile liquid in theclosed chamber will vary as the temperature of the air varies, and thatsuch variations of pressure will be transmitted directly to the pressurechamber 28,- and the pressure chamber 28 will be expanded in accordancetherewith.

The two chambers 28*29- form two members of a fluid pressure device andthey are coupled together by means of a lever33.

' This lever is pivoted at 34 to a part relatively stationary with theframe or casing 26, and is connected to the pressure chamber 29 by meansof a yoke 35 and set screw 36, and to the pressure chamber 28 by meansof a set screw 37. The expansion of the chamber 28 tends to move thelever in a clockwise direction as viewed in Fig. 2, about a pivotalsupport 34, while the expansion of the chamber 29 tends to move thelever in an anti-clockwise direction, as will be well understood byreference to the drawings.

At its upper extremity the lever 33 is engaged by a set screw 38 whichis carried by a link or yoke 50, the opposite end of which is acted uponby a spring 39. This spring is under normal compression and tends toforce the lever inward, i. e., in a direction to the left as viewed inFig. 2. At its extreme end the lever carries a portion 40 which in' its.engagement with a nipple 41 acts asa valve to open or close escapethrough the said nipple. This nipple ismounted in a portion of thecasing 26 in which there is a channel 42 leading to the main openingtherethrough, and hence is in open communication with the compressed airin the dew point cooler. A pipe 43 leads from this channel 42 to thefluid pressure motor 25 and by which compressed air is conducted to thefluid pressure motor for motive'purposes'. The passage 42 is restrictedat the point 44 whereby the air will only pass therethrough a little ata time. If the nip- .ple 41 be closed the compressed air in pass,-

ing through the restricted opening will I build up in the pipe 43 and inthe fluid pressure motor to operate it in one direction, while on theother hand, if the lever 33 be moved to a position wherein there will bea free opening through the nipple 41, the air previously employed asmotive fluid in the fluid pressure motor will be dischargedtherethrough, it being understood that the capacity of the nipple 41 issuch as to permit the fluid motor to exhaust therethrough even whilefresh motive fluid is being supplied through the passage 42 andrestricted opening 44. In other words, the opening through the nipple isof 'larger capacity than the restricted opening 44.

For the purpose of adjusting the instrument 12 the pivotal point 34 orfulcrum of the lever 33 may be adjusted as may also the tension of thespring 39. The tension of the spring 39 is regulated by the adjustmentofthe set screw 38 as will be well understood, while the means by whichthe pivotal point 34 is adjusted includes a bracket 45 longitudinallymovable along the casing extension 26 in which it is mounted, saidcasing extension having a slot 46 for receiving the bolt 47 by which thebracket 45 is secured in position, and a collar 48 along the lever 33, aset screw 49 being provided for securing it in its adjusted position,the said collar 48 being pivotally mounted between extending arms of thebracket 45 (see Fig. 5).

The operation of the apparatus is as follows: First the tension of thespring 39 is regulated by the proper adjustment of 'the' .which ismounted to slide longitudinally the temperature to which the air iscooled in the dew point cooler is the proper one to maintain the'propermoisture ratio at the at the time, it is because the cooling water isbeing delivered at the proper temperature and the apparatus will workjust as it is set. If the temperature, however, is too high the volatileliquid in the closed chamber will be expanded, and there will be anexcess of pressure in the closed chamber 32 and consequently in thefluid pressure chamber 28. The lever 33 will, therefore, move to theright .120 pressure at which the air is being employed as shown in Fig.2, the motive fluid will be vented through the nipple 41 from the motor25, and the valve 24 will be moved to a position wherein it will admit alarger quantity of refrigerated water to the pump and a relativelysmaller quantity of the relatively hot return water from the dew pointcooler; the temperature of the water supplied to the dew point coolerwill belowered and the air in the dew point cooler will be cooled to thelower point required .to maintain the required moisture ratio therein.On the contrary, if the temperature be too low the volatile liquid inthe closed chamber will be contracted, the expansion chamber 28 willcollapse, and the lever 33 will move under the influence of the spring39 and the pres sure upon the pressure chamber 29, to the .left asviewed in Fig. 2; the nipple 41 will be closed and air under pressurewill be admitted to the motor to move the valve 24 in the otherdirection wherein a larger proportionate quantity of the relatively hotwater and a smaller relative quantity of the refrigerated water will bedelivered to the pump and by it delivered to the dew point cooler. Bythis means a balance will be constantly established in the fluidpressure operated means, whereby the extent to which the air is cooledwill be in the proper proportion touthe pressure of the air to maintainthe proper moisture content therein, as has been explained above.

To comply with the foregoing conditions the expansible medium employedin the closed chamber 32 must be one whose expansion under temperatureis in such direct proportion to the pressure increases of the air as arerequired by such temperature increases to effect the result aforesaid.We have found that sulfur dioxid fulfils these requirements withsubstantial accuracy within the ordinary limits required. For instance,assuming that it be required to main tain a moisture content equal to21% grains per pound of air, or, in other words, 1.75 grains in a cubicfoot of air at its dew point, at atmospheric pressure, the pivotalcenter or fulcrum of the lever 33 will first be adjusted so that thedistance between it and the point at which the diaphragm 36 connectstherewith is .585 of the distance between the said pivotal center orfulcrum 34 and the point at which the expansion cham ber 28 connectswith the lever, while the spring 39 will be adjusted so that it opposesa pressure of 6.56 pounds per square inch of the effective surface ofthe expansion chamber 28 against the movement of the lever, at the pointat which the expansion chamber 28 connects therewith. Now assuming thegage pressure of the air (2'. 6.,

. the pressure in pounds per square inch above atmospheric pressure) tobe 7.95, the table given above shows that a temperature of 38 degreesFahrenheit is required in order that the moisture content shall beexactly that called for. At a temperature of 38 degrees Fahrenheit thecorresponding pressure which the sulfur dioxid will exert upon the lever33 at the point 37 will be 11.2 pounds. Subtracting the springresistance, viz., 6.56 pounds therefrom we have 4.64 pounds, andmultiplying this by the lever ratio of l to .585 we have 7.95 pounds tocounterbalance the air pressure at the point at which the expansionchamber 29 is connected with the lever. And this is the exact amount ofpressure which is applied by the air thereto at the time. Between 36 and50 degrees Fahrenheit in which the gage pressures corresponding theretofor maintaining 25% grains of water pressure per pound of air range from6.3 pounds per square inch to 21.10 pounds per square inch as is shownin the table given above, the variation in gage pressures is notexceeding about .3 of a pound, or assuming the gage pressures to beaccurate the variations in temperature from the exact requirements donot exceed .26 of .a degree.

In the diagrammatic View Fig. 6 in which the vertical lines representgage pressures in pounds per square inch, and the horizontal linesdegrees of temperature Fahrenheit, the curved lines A-B CD represent thevalues at any point between the extremes thereof required to maintain amoisture content of 2 grains, 1.75 grains, 1.5 grains and 1.2-5 grainsper cubic foot of saturated air at atmospheric pressure respectively,while the dotted lines ll -XY-Z represent the values actually given bythe use of sulfur dioxid, or similar fluid, acting upon the differentialpressure means in accordance with the temperature of the air inopposition to the pressure of the air, the spring tension and leverratio being also properly adjusted for the relative humidity required.It will be noted that the lines WVA, XB, YC, and ZD respectively verynearly coincide and that.their divergence from actual coincidencewithin. the limits of ordinary use is so small as to be substantiallynegligible. It will of course be understood that any volatile liquidwhose tension curve representing changes in pressure resulting fromtemperature changes parallels or approximates the pressure curve of airsuch as represents the increments of pressure lncrease therein whichwillmaintain a substantially uniform moisture content in the air at itsdew point, such as does sulfur dioxid, will be the precise equivalent ofsulfur dioxid when used in the present apparatus, and hence in referringto sulfur dioxid herein it will be understood that the term is not onlyintended to apply to sulfur dioxid itself but also to any other volatileliquids which are the equivalent thereof in the above sense.

It will be readily understood that the regulating device may begraduated to indibe as 1 is to .525, while the spring resistance will be8.45 pounds per square inch of the effective surface of the expansionchamber 28 upon the lever. At 1.75 grains relative humidity the leverratio will be .585 as aforesaid, and thev spring resistance 6.56 asalso.

stated above. At 1.50 grains relative humidity the lever ratio will beas 1 is to .538, while the spring resistance will be 4.68; While for1.25 grains humidity the lever ratio will be as 1 is to 4.74 and thespring resistance will be 2.86 and so on.

What we claim is 1. Means for varying the temperature of the air in airhumidifying and cooling apparatus,- as the pressure thereof varies,comprising a differential fluid pressure operated means, means forsubjecting one side thereof to the pressure of the air, means forsubjecting the other side thereof to thepressure of a fluid whosepressure increases upon increase of its temperature, in substantiallydirect proportion to the increase of air pressure required undercorresponding temperatime increases of the air, to maintain asubstantially uniform moisture content in the air at its dew point, andmeans controlled by the operation of the said differential fluidpressure means to vary the temperature of the air.

2. Means for varying the temperature of the air in air humidifying andcooling apparatus as the pressure thereof varies, com-' prising adifferential fluid pressure operated means, means for subjecting oneside thereof to the pressure of the air, an'adjustable spring for actingupon the fluid pressure operated means in the same direction, means forsubjecting the other side thereof to the pressure of a fluid .whosepressure increases upon increase of its temperature in substantiallydirect proportion to the increase of air pressure required undercorresponding temperature increases of the air to maintain a substantialuniform moisture content in the air at its dew point, and meanscontrolled by the operation of the differential fluid pressure-means tovary the temperature of the air.

3. Means for varying the temperature of the. air in air humidifyin andcooling apparatus as the pressure thereof varies, com

operated means in the same direction, means 05 for subjecting the otherside thereof to the' ressure of the air, an adjustable.

pressure of a fluid whose pressure increases upon increase of itstemperature in substantially direct proportion to the increase of airpressure required under corresponding temperature increases of the airto maintain a substantially uniform moisture content in the air at itsdew point, means for adjusting the relative effective force upon thefluid pressure operated means by the air and the said fluid, and meanscontrolled by the operation of the diflerential fluid pressure means tovary the temperature of the air.

4. Means for varying the temperature of the air in air humidifying andcooling apparatus, as the pressure thereof varies, com prising adifferential fluid pressure operated means, means for subjecting oneside thereof to the pressure of the air, means for subjecting the otherside thereof to the pressure of sulfur dioxid whose temperaturecorresponds to that of the air, and means con-.

trolled by the operation of the said differential fluid pressure meansto vary the temperature of the air.

5. Means for varying the temperature of the air in air humidifying andcooling apparatus as the pressure thereof varies, for the purpose ofmaintaining a uniform moisture content in the air, comprisingadifi'erential fluid pressure operated means, a closed chambercontaining sulfur dioxid and arranged in communication with the saidpressure means upon one side thereof, the said closed chamber beinglocated in the path of the cooled air, the other side of the saiddifferentially operated pressure means being subjected directly to thepressure of the cooled air.

6. Means for varying the temperature of the air in air humidifying andcooling appa ratusas the pressure thereof varies, for the purpose ofmaintaining a uniform moisture content in the air, including a dew pointcooler and a regulating means therefor comprising a lever, an expansionchamber engaging the lever at one point along the same, a closed chambercontaining sulfurd-ioxid and arranged in communication with the saidexpansion chamber," the said closed chamber being arranged in the dewpoint cooler in the path of the cooled air currents therein, anotherexpansion chamber engaging the lever at another point along the same andin opposition to the first said expansion chamber, the second saidexpansionchamand acted upon by the pressure thereof, a manuallyadjustable spring, bearing against 12.0 her being incommunication withthe air,

the lever in the direction in which the sec- 0nd said expansion chamberengages the same, and manually adjustable means for varying the ositionof the lever fulcrum.

7. .Means. or varying the temperature of the fair in ,air humidifyingand cooling apparatus as the pressure thereof varies, forithe purpose ofmaintaining a uniform moisture content in. the air, including a dewpoint cooler, means for supplying a cooling-medium thereto, and aregulator for varying the temperature of the cooling medium supplied tothe cooler as the pressure of the air in the cooler varies, the saidregulator comprising a'lever, an expansion chamber engaging the lever atone point along the same, a closed chamber containing sulfur dioxid,arranged in communication with the said expansion chamber, the saidclosed chamber being arranged in the dew point cooler in the path of thecooled air currents therein, anotherexpansion chamber engaging thelever'at another point along the same and in opposition to said.expansion chamher, the second said expansion chamber being incommunication with the air in the dew point cooler and acted upon bythepressure thereof, a manually adjustable spring bearing against the leverin the direction in which the second said expansion chamber engages thesame, and manually adjustable means for varying the position of thelever fl fulcrum.

JOEL IRVINE LYLE. EDWARD T. MURPHY.

Witnesses:

D. HOWARD HAYWOOD, LYMAN S. ANDREWS, Jr;

